InterviewSolution
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InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 1901. |
Arrange the following changes of energy during following phase transition in a proper order. Ice (0^(@) C) to "water "(50^(@)C) to "ice "(0^(@)C) (1) potential energy increases and kinetic energy remains constant (2) potential energy decreases and kinetic energy remains constant (3)potential energy increases and kinetic energy increases (4) potential energy decreasesand kinetic energy decreases |
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Answer» 4 23 1 (II) potentialenregyincrease and kientic energyincrease. (iii)potential decreaseand kinetic energy decreases. (iv)potential energy decreases and kineticenergyremains constant. |
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| 1902. |
Arrange in the proper order based on the atoms present in the following compounds: 2 g NH_(3), 2 g H_(2)O,2 g CO, 2g HCl |
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Answer» `CO lt HCl lt H_(2)O lt NH_(3)` |
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| 1903. |
Arrange in the order indicated for solid, liquid and gas. (i) effect of pressure-increasing order (ii) empty spaces in the particles-decreasing order (iii) tendency to flow- decreaing order (iv) thermal expansion- increasing order. |
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Answer» Solution :(i) SOLID, liquid, GAS (II) gas, liquid, solid (III) gas, liquid, solid (iv) solid, liquid, gas. |
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| 1904. |
Arrange different states of matter in the increasing order of their densities with appropriate reason. |
| Answer» Solution :In solidsm the molecules are TIGHTLY packed. Hence, the number of molecules PER UNIT volume is more and desity is the highest. In gases, the molecules are very loosely packed and the density is the least. Molecules of LIQUIDS are loosely packed, but intermolecular space is much less than that in gas. Hence, their denisities are generally less than SOLIDS, but more than gases. | |
| 1906. |
Are you familiar with the Bohr model of an atom? See the Bohr model of atoms of certain element, group I. What happens to the size of an atom when we move down the group? |
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| 1907. |
Are you familiar with the Bohr model of an atom? See the Bohr model of atoms of certain element, group I. Which one is the smallest? |
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| 1910. |
Are the mass of a molecule of a substance and its molar mass same? |
| Answer» SOLUTION :No, they are DIFFERENT | |
| 1911. |
Are elements identified by their atomic masses ? |
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| 1913. |
Archit dropped a crystal of potassium permanganate into two beakers A and B containing hot water and cold water respectively. After keeping the beakers undisturbed for some time what did he observe and why ? |
| Answer» SOLUTION :Potassium permangante crystals have purple colour. In a beak B containing hot WATER, the purple colour would spread more readily as compared to the beaker A which CONTAINS in it COLD water. Actually the kinetic energy of the PARTICLES increases with the rise in temperature. | |
| 1914. |
Aqueous solution of copper sulphate does not show Tyndall effect, while the mixture of water and milk shows Tyndall effect. |
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Answer» Solution :Colloids are big enough to scatter a beam of LIGHT passing through it. Copper sulphate solution is a true solution. The diameter of solute particles in it is LESS than 1 nm. The diameter of solute particles in solution of water and MILK is up to 1 nm to 100 nm. So this mixture is a colloidal solution. Hence, aqueous solution of copper sulphate does not show Tyndall effect but the mixture of water and milk shows Tyndall effect. |
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| 1915. |
Apply the law of mass action to the following equilibria : (a) PCl_(5) hArr PCl_(3)+Cl_(2) (b) 2NO+O_(2) hArr 2NO_(2) |
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| 1916. |
Apple contains malic acid. Orange contains .......... (a) citric acid (b) ascorbic acid |
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| 1917. |
Answer the following questions :(a) Name the two gases which are supplied in compressed form in homes and hospitals. (b) What is dry ice ? |
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Answer» Solution :(a) For answer, consult Q.7 (N.C.E.R.T. End EXERCISE). (b) LPG (Liquid Petroleum GAS) is supplied in homes while liquefied oxygen in HOSPITALS (c ) Solid carbon dioxide `(CO_(2))` is known as DRY ICE. It is so named as it does not wet a piece of paper or cloth. |
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| 1918. |
Answer the following in one line or two: (a) what is the maximum number of electrons that can be accomodated in the outermost energy shell in an atom? (b) on the basis of thomoson's model of an atom explain how an atom is neutral as a whole (c ) how many neutons are present in hydorgen atom? (d) do isobars belongs to the same elements? e ) An element has five electons in the M shell which is the outermost shell. write its electronic configureation. |
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Answer» Solution :(a) The outermostenergy shell in an atom can have a maximum of eight ELECTRONS (b) According to Thomson's model of an ATOMS all the PROTONS in an atom are present in the positively charged sphere while negatively charged elctronsare studded in this sphere .Since the electrons and protons are equal in number each carrying one unit charge the atom as awhole is ELECTRICALLY neutral (c ) Hydrogen atom has no neutron (d) No isolars belongs to different elements since they differ in their atomic number (e ) The electronic configuration of the element is K(2)L(8) M(5). |
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| 1919. |
Anode rays are deflected towards the negative plate in the presence of an electric field because they consist of _________particles. |
| Answer» SOLUTION :positively-charged | |
| 1921. |
Anhydrides of sulphurous acid and carbonic acid produce milkiness when passed through a solution of the same substance 'X' . When chlorine gas is made to react with the same solution 'X'. It gives a compound 'Y' having disinfectant action. Identify 'Y' and justify its use for the above purpose. |
| Answer» SOLUTION :ANHYDRIDES of sulphurous acid and carbonic acid are `SO_2 and CO_2`respectively. They produce milkiness on passing thorugh a solution of `Ca(OH)_2`. When `Cl_2` gas is made to REACT with `Ca(OH)_2,CaOCl_2` (bleaching powder) is formed. Bleaching power on dissociation in water gives `Ca(OH)_2, HCI` and HOCI.Hypochlorous acid being unstable decmposes of HCI and nascent oxygen which is RESPONSIBLE for bleaching action : | |
| 1922. |
a.Name the state of matter which is rigid. b. Name the process of conversion of solid state to liquid state. |
| Answer» SOLUTION :a. SOLID N. FUSION (or MELTING). | |
| 1923. |
Analyse the table given below. Write the chemical formula of the compound formed by A and B |
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| 1924. |
Analyse the table given below. Fill up the blanks |
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| 1925. |
Analyse the following statements and correct them if there is a mistake. The mass of an atom mainly depends upon the mass of the electrons and neutrons present in it. |
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| 1926. |
Analyse the following statements and correct them if there is a mistake. Down the group in .a periodic table ionisation energy decreases electronegativity increases. |
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| 1927. |
Analyse the following chemical equation and find out the element undergone oxidation, reduction, oxidising agent and reducing agent. S+O_2rarrSO_2 |
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Answer» OXIDISING AGENT -O REDUCING agent-S |
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| 1928. |
Analyse oxidation numbers in the given equation and list the oxidisingagent and reducing agent in the tabel given below. |
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| 1929. |
An unlit incense stick gives smell only when we come close to it, but on lighting the stick we get smell even far away from it. Why? |
| Answer» SOLUTION :Because the rate of diffusion of PARTICLES increases with increase in TEMPERATURE. | |
| 1930. |
An oxide of a non-metal 'X' is the anhydride of two oxy acids. Identify 'X' and the other two oxyacids. Also mention how the oxide is formed form the stable hydride of the same element. |
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Answer» Solution :The oxide of nitrogen which is a MIXED anhydride of its OXYACIDS is `NO_2`. The oxyacids are `HNO_2` and `HNO_3.NO_2` can be obtained from the stable HYDRIDE `NH_3` by its reaction with oxygen : `4NH_3+5O_2overset(PT)underset(900^@C)to 4NO+6H_2O2NO+O_2to 2NO_2` |
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| 1935. |
An iron piece is kept for some time in concentrated nitric acid and then removed. The iron piece now can neither liberate hydrogen from dilute sulphuric acid nor can it liberate copper to form copper sulphate. Explain with an appropriate reason. |
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Answer» SOLUTION :(i) reactivity of nitric acid (ii) reaction of nitricacid with IRON (iii) CHANGES in iron (IV) reactivity of iron |
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| 1936. |
An increase in atomic redius results in ________in the electron affinity of an element |
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| 1937. |
An incomplete form of the periodic table Is given below.(symbols are not real) Which element has the highest Ionisation energy? |
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| 1938. |
An incomplete form of the periodic table Is given below.(symbols are not real) Which are transition elements? |
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| 1939. |
An incomplete form of the periodic table is given below. Write answers to the questions connecting the position of elements in it. Which is the element that resembles E the most in its properties? |
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| 1940. |
An incomplete form of the periodic table is given below. Write answers to the questions connecting the position of elements in it. WhiCh among them are transition elements? |
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| 1941. |
An incomplete form of the periodic table is given below write answers in the question connecting the position of elements in it. Which element belongs to Noble gas elements? |
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| 1942. |
An impure sample of copper sulphate can be purified by ____ . |
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Answer» crystallisation |
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| 1944. |
An example of triatomic molecule is |
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Answer» Ozon |
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| 1945. |
An example of a substance that sublimes is _______. |
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| 1946. |
An element is sonorous and highly ductile. Under which category would you classify this element? What other characteristis do you expect the element to possess? |
| Answer» SOLUTION :The element is a METAL, It is expected to POSSESS the IMPORTANT characteristics of the metals. | |
| 1947. |
An element Z forms an oxide with formula Z_(2)O_(3) . What is its valency ? |
| Answer» SOLUTION :VALENCY is `3^(+)` | |
| 1948. |
An element X has a mass number 4 and atomic number 2. Write the valency of this element. |
| Answer» SOLUTION :The element X with MASS number 4 and atomic number 2 is HELIUM (He) .Ity has 2 electrons (maximum possible) in its only shell which is k shell .Therefore , the valency of the element is ZERO. | |
| 1949. |
Following conclusions are drawn by observing alpha-ray scattering experiment. Write the respecitve observations based on which these conclusions are drawn. (i) Non-uniform distribution of positive charge. (ii) Presence of positively -charged core or nucleus. (iii) Presence of large empty space in an atom. |
Answer» SOLUTION :
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| 1950. |
An element X belongs to group g II A and fourth period in the periodic table .Find out the atomic number of X and theelement which is placed just below x in the periodic table |
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Answer» SOLUTION :(i) elctonic configuration of x (ii) ATOMIC numbr of X based on periodic arrngement of ELEMENTS (iii) electronic configuration o of element below X (IV) atomic number of element below x |
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